This invention relates generally to an automatic feeding device for loading bulk material into packaging.
While a variety of bulk material feeding structures are known in the art, many such devices require that feeding be stopped after a predetermined weight has been reached so that the material-receiving packaging may be replaced. When such a stoppage occurs, time is lost and with many bulk materials a clumping together of the material results. This clumping leads to improperly packaged material, as by the inability to obtain firm weight accuracy and discrimination in the packaging. In order to permit a continuous flow of material, a number of devices have diverted the material fed to a catch hopper during the change in packaging. This diversion also may result in clumping, and its associated problems. Futhermore, a mechanism is then required to recycle the diverted material into the main flow.
In any such weighing and feeding system there is a direct relationship between speed and accuracy. For any given system, the slower the cycle time, the greater the accuracy and vice versa. Accordingly, I have found it desirable to have a system having more than one rate of feed, a faster rate at the beginning of the feeding procedure and a slower rate near the end, so that accurate weight monitoring can occur. The instant invention provides such a dual rate system.
Generally speaking in accordance with the invention, a continuous automatic feeding system is provided. Bulk material is continually fed without stoppage into a pair of alternately filled hoppers. The device has a vibratory feeder for moving the bulk material, and which has a narrow forwardly extending spoon for feeding the material at a relatively low rate. Mounted above each hopper is a deflector having first, second and third positions. In the first, fully projecting position of the deflector, no material may enter the associated hopper and all material will be diverted into the other hopper. In the second position (employed when filling is nearly completed), only the material flowing from the spoon will enter the associated hopper with the bulk of the material being deflected to the other hopper. In the third position, material flowing from both the spoon and the feeder is permitted to enter the associated hopper. Each hopper has an associated weigh cell which will control the operation of the deflectors and automatically discharge the fed material when the predetermined weight has been attained.
Accordingly, it is an object of this invention to provide improved automatic weighing and feeding apparatus.
Another object of this invention is to provide an improved automatic weighing and feeding device providing for continuous flow of bulk material.
Another object of this invention to provide an improved automatic feeding device that prevents clumping of the fed material.
Another object of this invention is to provide an improved automatic feeding device that permits a high feeding rate combined with highly accurate package weight content.
Another object of this invention is to provide improved automatic feeding apparatus that does not require interrupting the flow of material during a change of packaging.
Still other objects of this invention will become apparent upon a reading of the detailed specification to follow.